This is a rollover study to ACTG 320. The purpose of this study is dependent upon the particular group into which a patient enrolls: Group A To compare the time to confirmed virologic failure between the treatment arms. To evaluate the safety and tolerance of the treatment arms. Group B To compare the proportion of subjects who achieve plasma HIV-I RNA concentrations < 500 copies/ml, as assessed by the standard Roche Amplicor assay, at week 16 or to compare the absolute changes in plasma HIV-I RNA concentrations at week 16 across the treatment arms. To compare the safety and tolerance of the treatment arms. Group C To monitor plasma HIV-I RNA trajectory over time and determine the time to a confirmed plasma HIV-I RNA concentration > 2,000 copies/ml on two consecutive determinations. Group D To evaluate plasma HIV-I RNA responses at weeks 16 and 48. To evaluate to safety and tolerance of the treatment regimen.